Mixture for refining copper and its alloys



UNITED STATES.

PATENT OFFICE.

GEORGE G. MULLINS, OF LOS ANGELES, CALIFORNIA.

MIXTURE FOR REFINING COPPER AND ITS ALLOYS.

SPECIFICATION forming part of Letters Patent No. 413,535, dated October1889.

Application filed August 6, 1889. Serial No. 319,885. (No specimens.)

To aZZ whom it may concern:

Be it known that I, GEORGE GATEWOOD MULLINS, a citizen of the UnitedStates, re siding at Los Angeles, in the county of Los Angeles and Stateof California, have invented certain new and useful Improvements inMixtures for Refining Copper and its Alloys; and I do hereby declare thefollowing to be a full, clear, and exact description of the invention,such as will enable others skilled in the art to which it appertains tomake and use the same.

The object of this invention is to render more fusible, refine, andimprove copper, or copper and other metals in admixture to form alloys,to remove the dross, scoria, or slag, to prevent porosity, to harden andtoughen the metal, and greatly increase its tensile and resilientstrength.

The invention relates to the treatment of copper alone, or of copper andits alloy metals, with a peculiar flux, detergent, and auxiliary, whichis composed of certain parts of purest native silica, (SiO,,) floorspar,(OaFl carbonate of potash, (K 00 and tungstate of sodium, (Na,WO,+2H O.)These elements are first carefully crushed to a fine powder, and thenall carefully compounded together in about the proportions of four (4parts silica, three (3) parts fluor-spar, two (2 parts carbonate potash,and one (1) part tungstate of sodium.

Those skilled in the art to which this invention relates will understandthat the compound is chiefly a flux and-detergent, and will determine bytrial what quantity of the mixture to use for any given charge.

In applying my inventionI use this method for making what I callsilicated copper, brass, or bronze. On the bottom of crucible, or on thebed of reverberatory furnace, I place from one to ten per cent. of thesaid mixture, according to character and weight of metal charged. Whenall is molten, I stir the bath thoroughly, allow it to remain quiet afew moments, skim off the scoria or dross, then proceed in the usualmanner; orI place from one to ten per cent. of the mixture carried inpaper bags into the already molten metal, stir thoroughly, and thenproceed as usual. However, I would not confine myself to any fixedproportion of the parts in the mixture, or to the use of any limitedquantity of the mixture, or to any one special way of applying it to themetal. These must vary with diiferent conditions. What may be theinfluences of these several elements, separate or combined, whatchemical reactions may take place in the high temperature of crucible orfurnace, are problematic questions belonging to scientific theory andhave not yet been settled by adequate investigation; but as practicaland important economical results I have noted that this treatment withsaid compound flux or detergent makes the whole charge more fusible,causes the adulterant material in the bath to rise quickly to the top,while the cleansed metal subsides, dissolves and removes the oxides, andthus enables the several metals to combine chemically and form a truealloy, which they cannot do so long as any oxidized substance ispresent. It removes porosity, toughens and adds greatly to the tensileand resilient strength of copper and of copper alloyed with othermetals. Y

This special mixture and process for the treatment of copper and itsalloying metals is the result of study and experiment through manyyears.

I am aware that artificial silicate-such as crushed glass-and fluor-sparhave been used for certain purposes by copper and brass workers; but Ido not know that either the mixture of powdered pure native silica andfluor-spar or the compound of silica, fluorspar, carbonate of potash,and tungstate of sodium has ever been used by any one else for saidpurpose in metallurgy.

What I claim then as my invention is-- The mixture of silica,fluor-spar, carbonate of potash, and tungstate of sodium, insubstantially the proportions set forth, to be used GEORGE e. MULLINS.

Witnesses:

GRANVILLE E. HARRIS, DWIGHT F. CAMERON.

